Saudi Arabia, the United Arab Emirates, Egypt and Bahrain say they are severing diplomatic relations with Qatar.

The Saudi kingdom made the announcement via its state-run Saudi Press Agency early today, saying it was taking action for what it called the protection of national security.

The three Gulf states gave Qatari visitors and residents two weeks to leave their countries, Reuters news agency reported.

Saudi also closed the border and halted air and sea traffic with Qatar, urging "all brotherly countries and companies to do the same".

The statement appeared to be timed in concert with an earlier announcement by Bahrain, which was similarly cutting ties and halting air and sea traffic between the two countries.

Bahrain's foreign ministry issued a statement saying it would withdraw its diplomatic mission from the Qatari capital, Doha, within 48 hours and that all Qatari diplomats should leave Bahrain within the same period.

Egypt also announced the closure of its airspace and seaports for all Qatari transportation "to protect its national security", the foreign ministry said in a statement.

Etihad Airways, the UAE's flag carrier, said it would suspend flights to and from Qatar beginning tomorrow morning.

However, it was not immediately clear how today's announcement would affect other airlines.